New Delhi, April 21 (IANS) An indigenously-built Dhruv Advanced Light Helicopter (ALH) of the Indian Army, with four crew members, went missing in north Sikkim Thursday leading to fears that it may have crashed.

 
 The helicopter went missing near Shiv Mandir in the Lachung valley of the state at 11.20 a.m., an officer in the army headquarters here said.
 
 This is the first Dhruv that was operational with the Indian armed forces to have got into trouble since the chopper fleet was inducted into the air force, army and navy beginning 1998, he said.
 
 The chopper, carrying two army pilots, a junior commissioned officer and a soldier, had taken off from Sevoke Road near Siliguri in West Bengal around 9.50 a.m. Inclement weather was blamed for the chopper losing communication with the base.
 
 Another Dhruv helicopter, which had also taken off at the same time from Sevoke Road, has reached its destination in Shiv Mandir safely, the officer said.
 
 Army units at Chungthang, about 22 km away from the area where the Dhruv lost touch with the ground-based air controllers, have been rushed to carry out a search and rescue operation, he added. But their search has been hampered by adverse weather condition.
 
 The incident comes two days after a commercial helicopter crashed in Arunachal Pradesh. Seventeeen people were killed when the Mi-172 helicopter of Pawan Hans Helicopters Limited crashed while attempting to land at Tawang. The cause of the crash is yet to be ascertained.
 
 Designed and manufactured by the public sector Hindustan Aeronautics Limited, the ALH was first inducted into the Indian Air Force (IAF) for search and rescue, emergency airlift, air ambulance, evacuation, payload deliveries in high altitude posts and carriage of men and material.
 
 The choppers were later inducted into the army and navy too for similar roles.
 
 There were two incidents in the past involving Dhruvs - one of the seven sold by India to Ecuador air force crashed in October 2009 and another belonging to the Indian Air Force was forced to land due to a technical snag while rehearsing for the February 2010 'Vayu Shakti' air power demonstration near Jaisalmer in Rajasthan, the officer added.